VP540 whole black head fires randomly

[nwbee]

This has been happening for a while but not anywhere near this bad. I would get a small line every few prints that could barely be noticed. Now I get them every print. They are always in the same area of the printer. Which is shown in the first picture. The others are just zoomed in pics of different samples. I have also included a print test. I know that the black head needs replacing because it has tested like this for a very long time. The quality of the black has been affected by this for a while but I can live with the small quality issues. The problem is that the lines are big and all the way down now. They are always 1" long but the width varies. They are always put down in 1 pass. Its not like the printing that goes on in passes. It will suddenly lay down the whole line/bar on the media and sometimes overlap on other random lines. I have cleaned the encoder strip and it didnt help. I suspect it could be the print head, controller board, or even one of the many ribbon cables. I really would like to narrow it down before I replace anything. I called Roland and they told me to contact the vendor. The vendor's tech suggested things that I already tried and doesn't know what it is. They can come out and replace a bunch of stuff, but I can do that also. Any suggestions would really be appreciated.

 

[CS-SignSupply-TT]

If the VP540 is still under Roland warranty, you should INSIST that the VENDOR perform Roland Warranty service on the printer.

 

[CS-SignSupply]

How long have you had this printer? Warranty?

Does this pattern change if you change the print quality? HighSpeed, Standard, High Quality?

I would also wonder about the trailing cable.

To troubleshoot a little... power off and and Unplug. Then switch the ribbon cables (black and cyan). Then power back on and try again.

 

[artbot]

beware, you are about to hurt that printer.

most likely loose data cable. turn the printer off, switch off, unplug, press the front button four times. reseat the cables.

 

[nwbee]

It is 4 years old and out of warranty. I also suspected the cable in the back but not sure how to test it. Just a little while ago, it started doing it on other sections. Its not really a pattern but random lines but it does it with different settings as well. I have already reseated all of the ribbon cables that I can find. I actually thought about swapping the cyan and black but I want to be sure that it will not damage the print heads (more). Do I have to change the settings in service mode or can I just swap the ribbon cables for a quick test? Thanks for your help.

 

[J Hill Designs]

swap cables and see if the data problem transfers to the cyan head (do power down as artbot suggests first!)

 

[artbot]

also when you are swapping there is a specific pattern that you have to retain. the cables have to be in pairs and stay in their top/bottom positions...

as an example look at this rendering for a jv3 160sp. see how the cables move together.

also, this is a pic of my loose cable issue. it did the little squares then went nuts.

 

[nwbee]

Ok i did the swap and I guess the print head can be ruled out. I have also tried different computers and different software to create file, just in case. I've disconnected and reconnected the ribbon cables that I can see and still same issue. Here are the pics. Any other suggestions would be appreciated.

 

[artbot]

so as far as isolating. does this print issue happen in all the heads? i see it doing it with black, then later with cyan. and which data cables did you swap. the swap can determine a number of things. if the head is bad, if the ribbon is bad, if the port (mimaki calls it a slider board, think roland calls it a carriage board?) is bad.

did you do the data swaps in such a order that you can remove and or repeat the issue?

 

[nwbee]

Well I swapped the black and cyan at the carriage board and it started doing it only with cyan instead of black. That eliminates the ribbon cables (to the heads) and the print head. So I do suspect it is the "carriage board" or hopefully not the "network" board. Still checking for and reseating and other cables. Does anybody where to get the carriage boad? Thank you again for your help.

 

[artbot]

no you have one more thing to do. if the ribbons making the black weird went to the cyan port and made the cyan weird. you then completely take out the cables (label them). and put the cyan cables on your black head and your black cables on your cyan head (including the carriage board ports. you are transplanting the data cables). if the issue moves also to the cyan head (and this is in a non data swap print), then your black cable/s are bad and both heads are fine and both carriage board ports are fine. if of course the black head malfunctions with the cyan cables to it. then you do have something wrong with that black carriage board port or something worse. if so, macmedia diagnoses for $40 and rebuilds carriage boards for $200. they are very honest. i sent them a slider board once and they sent it back saying it was fine. which it was.

 

[nwbee]

OK, I figured out the issue. I was going to replace the carriage board and ordered it overnight delivery. Luckily, it was out of stock and would take about 5 days to get here. Since I couldnt wait, I decided to try one of my original ideas and switch around all 3 of the long cables in the back that go from main board to carriage board. I figured this might be the issue since it was only doing it in certain area. Just to warn anybody that wants to try this, it is a nightmare. You have to take off all kinds of things and unbend and rebend and reposition the cables. After doing this, the lines are gone. Now there is a small problem with the quality of the blue. I am going to just replace all 3 of them because to figure out which one is responsible means I have to swap them in pairs and put everything back together and try again at least 4 more times including the final replacement. I'm more likely to damage them or something else so I'll just change all 3 once and for all. Its gonna cost a little more than the carriage board but I would honestly rather pay more than do it any more times than absolutly needed. Again thank you all for your help.

 

[Papajo]

There is a shortcut on the data cables most probably those between the main board and the carriage board. Sometimes this is caused by a ferrite ring around the cables not being properly attached. The friction of the ferrite on the cables damages the plastic coating of the data cables and shortcuts the data lines.

You will most likely have to replace the three data cables between the main board and the head carriage.